1. Field of the Invention
This invention relates generally to the art of modulating the flow through a passage of a compressible or non-compressible fluid. More particularly, the invention relates to an improvement in fluid flow control devices, such as valves or regulators, to conduct a pressurized fluid relatively noiselessly through a substantial pressure drop.
2. Prior Art
A wide variety of mufflers, valves or regulators, and the like, have heretofore been devised for conducting pressurized liquids or gases through substantial pressure drops in a manner to minimize noise. Webb, et al., U.S. Pat. No. 3,731,903 discloses a cannister containing brazed together arrays of precisely stacked balls of various diameters to define a multiplicity of flow restrictions and expansion areas for a liquid stream. In Kubota U.S. Pat. No. 3,917,221 the flow restrictor geometry takes the form of a plurality of coaxially nested concentric peripherally grooved perforate sleeves. Engel, et al., U.S. Pat. No. 4,024,891 discloses a noise abating plug for a control valve comprising a perforated sleeve that is spanned by a plurality of spaced apart perforated discs.
Typically, the prior art devices require expensive custom made components and/or laborious and expensive assembly techniques to achieve a required orientation of the parts relative to one another, and they do not lend themselves to the ready development of a wide variety of types and sizes of inexpensive sound suppressing flow restrictors.